Three unreleased songs by Prince are being auctioned off as part of a larger collection of items related to the “Purple Rain” musician.

The songs are contained on a cassette tape recorded in the 1970s. Along with the three unreleased songs, the tape contains three early versions of songs he would later release, including “an early, acoustic version of ‘So Blue,'”; an early version of “Gotta Broken Heart Again,” which would later appear on his “Dirty Mind” album; and “a very early, virtually unrecognizable version of ‘Sometimes It Snows in April,” which would be featured on “Parade.”

Of the unreleased songs, two are described as containing “bouncy, upbeat choruses and risque lyrics,” while the third “features heavy guitar distortion and a chorus that includes very candid sexual pleas from Prince.”

The minimum bid on the tape is $20,000.

Prince’s collaborator and guitarist Dez Dickerson, who provided the tape, said of the offering, “Prince originally gave me the cassette in late 1978 because he wanted me to listen to a record he had recorded on side A (a female-fronted funk band whose name I don’t remember now). Sometime during the next year or so, I used the A side to record some scratch bass and guitar parts for songs I was going to be recording for a rock/power pop demo I was doing, recording over the original content (you can still hear a snippet of the funk record at the end of the side). On side B, Prince had his work versions of 6 songs, which I left intact for, at that time, unknown reasons (obviously, we now know it preserved a piece of musical history).”

Other items in the auction include outfits worn by the musician, china from his wedding (emblazoned with Prince’s “Love” glyph), a 1959 acoustic guitar use by Prince to write and record early demos, and the diamond engagement ring that Prince proposed to his wife Mayte Garcia with, “accompanied by 5 handwritten heart notes, which Prince used to lead her on a romantic journey to the ring.”

That one will set you back $100,000.

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